This invention pertains to a lock system for an article of furniture such as a file cabinet, desk pedestal or the like having one or more drawers or self-storing doors in a stacked arrangement.
In a drawer locking system, it is common to provide a lock bar which is mounted to the structure of the cabinet for vertical movement between a locked position and an unlocked position. The lock bar includes locking studs or the like which move vertically during vertical movement of the lock bar, and the studs are movable into and out of engagement with slots formed in lock brackets mounted to the drawers.
Many prior art lock systems are known for providing vertical movement of the lock bar between its drawer locked and drawer unlocked positions in response to key-operated rotating movement of an actuator mechanism. Some such systems include a bevel gear arrangement for imparting vertical movement to the lock bar. While this type of arrangement operates satisfactorily, it is time-consuming and expensive to assemble, and requires extremely close tolerances in assembly in order to insure proper operation. Other such systems including very complex mechanisms having numerous moving parts, which again are difficult to assemble and require close manufacturing tolerances.
It is an object of the present invention to provide a lock system which is relatively simple in its construction and operation. It is a further object of the invention to provide such a lock system which is relatively easy to assemble, thereby reducing installation time. It is a further object of the invention to provide a lock system in which close manufacturing tolerances are not required, yet which nonetheless provides reliable and highly satisfactory operation.
The invention is used in connection with an article of furniture, such as a file cabinet, drawer pedestal or the like, having a front, a back and a pair of spaced sides. The article of furniture further includes at least one drawer or door and a movable lock member selectively movable between a locked position and an unlocked position.
In accordance with one aspect of the invention, a lock system for such an article of furniture includes a rotatable operator-controlled actuator mechanism mounted toward the front of the article of furniture; a pivotable lifting and lowering mechanism interconnected with the lock member for vertically moving the lock member between its locked and unlocked positions; and an operating mechanism interposed between the actuator member and the lifting and lowering mechanism for pivotably moving the lifting and lowering mechanism in response to rotation of the actuator member. The operating mechanism includes a first member interconnected with the actuator member, and an arrangement for converting rotation of the actuator member into linear movement of the first member along a front-rear axis. The lifting and lowering mechanism is interconnected with the first member, and is pivotable in response to the front-rear linear movement of the first member to provide vertical movement of the locking member between its locked and unlocked positions. The arrangement for converting rotation of the actuator member into linear movement of the first member includes a lead screw interposed between the actuator member and the first member. The actuator member is mounted for rotation within a barrel having an open end, and the lead screw includes a head disposed within the barrel and extending through its open end. A key shaft is mounted between the actuator member and the head of the lead screw from imparting rotation to the lead screw in response to rotation of the actuator member. The first member, which is movable in a front-rear direction, includes a threaded socket within which the threaded portion of the lead screw is received. The operating mechanism further includes a toothed rack member mounted to the socket for front-rear movement along with the socket in response to rotation of the lead screw, a rotatable toothed pinion having teeth which mesh with those of the toothed rack member, and a shaft extending between and interconnecting the pinion with the pivotable lifting and lowering mechanism.
In accordance with another aspect of the invention, a panel is mounted within the article of furniture adjacent the drawer, and a surface of the lock member is adjacent to and facing the panel. A locking stud is mounted to the lock bar, extending through a slot formed in the panel for movably mounting the lock bar to the panel. A lever is pivotably mounted to the panel and interconnected with the lock bar. Pivoting movement of the lever causes movement of the lock bar between its locked and unlocked positions. An operator-controlled actuator and operating mechanism, as summarized above, is interconnected with the lever for selectively imparting pivoting movement to the lever. The lever is mounted to the panel by means of a pin which defines the pivot axis of the lever, with the pin being received within an opening formed in the panel. The lever includes a first arm extending outwardly from the pin and terminating in an outer end, and a second arm extending from the outer end of the first arm along an axis substantially parallel to the pivot axis of the lever as defined by the pin. The second arm is engaged within a slot formed in the lock member, and is provided with an enlarged head which functions to retain the second arm within the slot. The opening formed in the panel, within which the pin is received, is also in the form of a slot extending along a longitudinal axis substantially perpendicular to the longitudinal axis of the lock bar. The lever further includes structure defining an internal passage within which the shaft associated with the actuator and operating mechanism is received, with the shaft being pivotable in response to the actuator and operating mechanism for selectively imparting pivoting movement to the lever.
The invention further contemplates a method of mounting the lock member and the pivotable lever to the article of furniture, substantially in accordance with the foregoing summary.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.